Arno Botha will not be joining Ulster, with the province deciding not to sign the injury-plagued Bulls loose forward.

Ulster announced in January that they would sign Botha on a two-year contract but after sustaining a knee injury last month the deal will not go through.

"It's unfortunate for both Arno and Ulster Rugby that we've had to come to this decision as we were looking forward to welcoming him to Kingspan Stadium. However, we have acted with the best interests of team performance in mind," said Ulster Operations Director Bryn Cunningham.

"We have meticulous processes in place for all player recruitment and having commissioned an independent medical assessment in South Africa, it was recommended that the risk had increased following his most recent injury. This view was shared by our own medical team.

"Everyone associated with Ulster Rugby sincerely hopes that Arno will go on to have a long and successful career.

"Once this decision was reached, we compiled an extensive list of potential targets and we will announce a signing to bolster the forward pack in due course."